Introduction The Sony/Tektronix Type 323 Oscilloscope is a solid-state portable instrument that combines small size and light weight with the ability to make precision waveform measurements. The instrument is mechanically constructed to withstand the shock, vibration and other extremes of environment associated with portability. A DC to four megahertz vertical system provides calibrated deflection factors from 0.01 to 20 volts/di vision (0.001 volt/division minimum with reduced frequency response). The trigger circuits provide stable triggering over the full vertical bandwidth. The horizontal deflection system provides calibrated sweep rates from one second to five microsceonds/division. A X10 horizontal magnifier allows each sweep rate to be increased 10 times to provide a maximum sweep rate of 0.5 microseconds/ division in the 5 ,as position. X-Y measurements can be made by applying the vertical (Y) signal to the VERT INPUT connector and the horizontal (X) signal to the EXT TRIG OR HORIZ INPUT connector (TIME/DIV switch set to EXT HORIZ, Trig/Horiz Coupling switch set to EXT TRIG OR HORIZ). The Type 323 can be operated from any one of three power sources; AC line, external DC or internal recharge- able batteries. A power regulator circuit assures that instrument performance is not affected by variations in internal battery charge level, applied DC voltage or AC line voltage and frequency. Maximum total power consumption is 4.5 watts for external DC or internal battery operation and 14 watts maximum when operated from an AC line. Operation from an AC line also provides full or trickle charging for the internal batteries.